Let-off mechanism for looms



Patented May I6, |899.

l 0. W. SCHAUM.

LET-DFF MECHANISM FDR LOOMS.

(Application filed Jan. 17, 1899.)

@No Modal.)

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NITED STATES PATENT OEEICE.

OTTO IV. SCI-IAUM, OF PIIILADELPHIA, PENNSYLVANIA.

LET-OFF MECHANISM FOIR LOOMS.v

SPECIFICATION forming part of Letters Patent No. 625,206, dated May 16, 1899.

Serial No. 702,480. (No model.)

To all whom t may concern:

Be it known that I, Or'ro W. SCHAUM, a citiaen of the United States, residing in Philadelphia, county of Philadelphia, in the State of Pennsylvania, have invented certain new and useful Improvements in Let-Off Mechanisms for Looms; and I do herebydeclare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, and to figures of reference marked thereon, which forms a part of this specification.

My invention relates to let-off mechanisms for looms, and especially for narrow-ware looms; and it constitutes an improvement upon the device of this nat-ure which was patented to me under Letters Patent No. 584,793, dated June 22, 1897.

In the above-mentioned patent weighted levers are employed as means for controlling the tension upon the warp. The principal object of my invention is therefore to so oonstruct and relatively arrange these levers as to not only render them susceptible of greater relative movement, but also by virtue of their peculiar arrangement to materially improve upon the analogous devices in so far as the desired uniform strain upon the warp is concerned.

In the above-mentioned patented invention it was practically impossible to secure at all times a uniform tension upon the warp, for although this might be accomplished while the loom was being -operated under normal circumstances-that is to say, in a forward direction-when the machine was reversed or the warp let back in order to pick out the web the weight of practically but one'set of levers instead of both sets, as under said normal or forward operation, would be acting upon said warp. Furthermore, the arrangement of the levers was such that whenever the levers were separated or opened the separating or opening action was dependent entirely upon one and not both of said levers. As a result, the action upon the warp was different vwhen the machine was operating forwardly from what it was when it was operating backward, and the web consequently varied in width.

In View of the V foregoing considerations, therefore, the'invention hereinafter particularly described consists in the improved letoff mechanism and in the combination and arrangement of its parts, substantially as will be herein described, and nallyembodied in t-he clauses ofthe claim.

In the single figure of the accompanying drawing my improved let-off mechanism is shown in side elevation, being mounted, as usual, at the rear of the loom, a portion of whose framework is shown partially in section and partially in dotted lines.

In said drawing, 1 indicates the rear portion of the framework of the loom, and 2, 3, and 4 designate three of the cross beams or rails which form a part of the frame and which support my improved let-off mechanism.

5 represents one of a pair of sidevframes or supports having several arms whereby it is secured to the Various cross beams or rails above mentioned. In bearings or recesses 7, formed at suitable intervals in saidV side frames, are journaled the ends of the various beam-shafts. The shafts for the ground warpbeams 8 and 9 are designated by the numerals 10 and 11, respectively, andthe shafts for the edge and binder warp-beams 12 and 13, the latter of which beams is situated above the former, are designated by the referencenumerals 14 and 15, respectively.

16 designates levers each of which constitutes one of a pair that are fulcrumed in the side frame 5 at points 17 below the bearings 7 of each ground warp-beam, and 1S and 19 each designate one of a pair of similarly-fulcrumed levers, the former being for the edge warp and substantially like the levers 16 in shape and the latter being for the binderwarp and differing slightlyin form from said lever 16. The various pairs of levers are connected by one or more rods 20, which servev as racks for weights 2l. y

22 indicates levers which are fulcrumed upon and are preferably shorter than 'the various levers already described and each ofwhich is provided upon its under side with a heel or lug 23, with which the longer levers IDO are adapted to contact when raised. Each of the warp-beams is provided at its ends with a peripherally-grooved disk 24, in which fit flexible friction devices, each consisting of a band 25, provided at one end with a threaded pin 26, having an adjusting-nut 27 and extending, in the case of the'two lower or ground I warp-beams, through enlargement 28 on the end of projections 29, formed upon the side frames 5, and in the case of the upper or binder and edge warps through projections 30, formed on said side frames. The forward end of each band 25 is provided with a hook 3l, engaging a bent pin 32, formed upon each lever 22.

It should be remarkedv that the levers 22 should be so fulcrumed in the longer levers that their fulcruming-points will be somewhat contiguous to the points of securing the bands to said levers, so that when their rear ends are. actuated their forwardends will haveappreciable movement. It should also be remarked that the shorter levers 22 are angular in shape, their free ends being held by the bands 25 considerably above their fulcrumed ends.

At the ends of the shorter levers and upon rods 33, connecting them, and in vertical brackets 34, integrally formed with each longer lever, and upon rods 35, connecting corresponding brackets, are journaled rollers 36 for the warp. Said warp extends from' each beam to and over the rollers 36, carried by the levers, and then over other rollers 37, suitably journaled in a pair of arms 3S, mounted on the beam 2.

With regard to the construction of the.

longer levers it should be stated that each of the lower three of said levers maybe adjustably fulcrumed upon the side frames 5 by virtue of the provision of a series of fulcruming-apertures 39 and that the uppermost pair of levers I9 is provided at the rear end with a connecting-bar 40, serving as a rack for the counterbalance-weights 4l.

In View of the foregoing it will be seen that the motion of the shed in opening will act to raise the longer levers into contact with the heels or lugs 23 of the shorter levers, thereby raising the latter and tending to throw out of operation the braking device for the beams, which each disk and band therefor constitutes. This tendency to throw out of operation the braking device is, however, immediately counterbalanced by the consequent tendency of the longer levers to fall. Thus the tension is preserved constantly uniform. Moreover, the peculiar arrangement of the levers, which I have hereinbefore described, permits of a comparatively great movement of the longer levers and an increasing of the distance between them and the shorter levers, leaving to the shorterlevers for the most part the function ot' directly affecting the operation of the braking device. Furthermore,

when each longer lever drops it will be seen that the fulcrumed end of the shorter lever will also drop, said shorter lever moving about its pin 32 as a fulcruming-point when" said lever is moved downwardly as tar as the band 25 will permit. The effect of the dropping of the rear or fulcrumed end of this longer lever is to augment the increasing of the distance between the levers, which would otherwise be the function of the longer lever' alone. Furthermore, it should be remarked that whether the loom is in normal or active operation or not-aa for instance, when it is necessary on account of an error or mispick to pick out the web and let the warp backthe tension is constantly uniform, for though the lower or longer lever may drop considcrably its weight is always more or less acting on the warp in conjunction with that of the shorter lever.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-- l. In a let-olf mechanism for looms, the combination, with a frame and with a warpbeam journaled therein, of a pair of leversfulcrumed in said frame, -another pair of levers fulcrumed in said first-named levers and extending over the same and bands having frictional contact with and surrounding a portion of said beam, said bands being connected to the frame at one of their ends and to the. last-named pair of levers at the other of their ends,.the warp having a substantially over and under engagement with the free ends of the shorter and longer levers respectively, substantially as described.

2. In a let-off mechanism for looms, the combination, with a frame and with a warpbeam, of a pair of levers fulcrumed therein at or near one of their ends, another pair of levers fulcrumed in said iirst-named levers and extending over the same, and bands having frictional contact with and surrounding a portion of said beam, saidv bands being connected to the frame at one ot their ends and to the last-named pair of levers at the other of their ends and between the fulcrumingpoint and the free end ofY said pair of levers, the warp having a substantially over and under engagement withithe free ends of the shorter and longer levers respectively, substantially as described.

3. In a let-oft mechanism for looms, the combination, with a frame and with a warpbeam, of a pair of levers fulcrumed between their ends to said frame, counterbalance-` IOO rro

625,206 s v a named pair of levers at the other of their ends have hereunto set my hand this 12th day of and between the fnlcrnming-point of said pair January, 1899. of levers, the warp having a substantially over and under engagement with the free 'OTTO 7' SCHAUM' 5 ends of the shorter and longer levers, respec- Vitnesses:

tively, substantially as described. ALFRED GARTNER,

In testimony that I claim the foregoing I JOHN W. STEWART. 

